The present invention relates to a novel stilbene derivative which is suitably used as an electron charge transferring material (particularly hole transferring material) in a solar battery, an electroluminescence device, an electrophotosensitive material or the like, and a method for producing the same.
In image forming devices, various photoconductors having a sensitivity at the wavelength range of a light source used in said devices have been used. The organic photoconductor has widely been used because of its advantages such as easy production in comparison with a conventional inorganic photoconductor, various selective photosensitive materials (e.g. electric charge transferring material, electric charge generating material, binding resin, etc.) and high functional design freedom.
Examples of the organic photoconductor include a single-layer type photoconductor wherein an electric charge transferring material and an electric charge generating material are dispersed in the same photosensitive layer, and a multi-layer type photoconductor comprising an electric charge generating layer containing an electric charge generating material and an electric charge transferring layer containing an electric charge transferring material, which are mutually laminated.
As the electric charge transferring material used in the above photoconductor, a stilbene derivative is disclosed in Japanese Patent Laid-Open Publication Nos. 50-31773 and 7-244389.
However, since the stilbene derivative disclosed in the above patent publications is normally inferior in compatibility with a binding resin and is not uniformly dispersed in the photosensitive layer, electric charges hardly move. Therefore, although the above stilbene derivative itself has high electric charge mobility, when using this stilbene derivative as an electric charge transferring material, the characteristics can not be sufficiently exerted. Accordingly, the residual potential of the photoconductor becomes higher and the photosensitivity was not sufficient.